It’s an old song called "Accentuate the Positive." It was sung by Bing Crosby and several others. It was written by Johnny Mercer. This is the chorus to it.
You've got to accentuate the positive
Eliminate the negative
And latch on to the affirmative
Don't mess with Mister In-Between
I think that mister-in-between is a flevil; either the flesh (our old human nature) or the devil or both. Either way don’t mess with him.
For assuredly, I say to you, whoever says to this mountain, ‘Be removed and be cast into the sea,’ and does not doubt in his heart, but believes that those things he says will be done, he will have whatever he says. (Mark 11:23)
Because of your unbelief; for assuredly, I say to you, if you have faith as a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible for you. (Matthew 17:20)